Slides in this set

Slide 1

Slide 2

Keywords Food Chain ~ a sequence (usually shown as a diagram) of feeding relationships between organisms, showing who eats what and the movement of energy through trophic levels. Biomass ~ any organic, non fossil material ­ e.g vegetable matter or animal waste which can be used as fuel. An example would be generation of gas from decomposing organic waste. Habitats ~ places inhabited by communities of living things Photosynthesis ~ is the process where green plants use water and carbon dioxide and sunlight to produce carbohydrates (stored energy) and release oxygen (as a by product).…read more

Slide 3

Keywords Ecosystem ~ a community of animals, plants and micro-organisms together with the habitat they live in. Predator ~ an animal that hunts, kills and eats other animals for food. Prey ~ organisms that predators kill for food. Species ~ used in the classification of living organisms, referring to related organisms capable of interbreeding. Population ~ a group of members of a single species living in a habitat.…read more

Slide 4

Populations & Pyramids Food chains show the feeding relationship in a habitat. Pyramids of biomass are charts that show the mass of living organisms at each step in a food chain. Energy is lost moving up in a food chain, and this limits the length of the chain ­ so its more efficient to feed people with plants than with meat. Organisms usually compete with each other for resources. The populations of predators and prey are interrelated.…read more

Slide 5

Food Chains A food chain shows who eats what in a particular habitat. For example, grass seed is eaten by a Vole, which is eaten by a Barn Owl. The arrows between each item in the food chain always points from the food to the feeder. This is the direction in which the energy flows in the food chain.…read more

Slide 6

Food Chains Food chains always start with producers, which are almost always green plants. The other organism in the food chain are consumers ­ they get all their energy and biomass by consuming (eating) other organisms. Most food chains are quite short, and they rarely consist of more than four steps. This is because a lot of energy is lost at each step. After about three steps, very little energy is still available for use by living organisms. This also explains why there are few organisms at the top of food chains, compared with those lower down.…read more